1. Field of the Invention
The present invention relates to a remote power source control, and more particularly to a method and apparatus for turning on and off remote power sources of a plurality of information processing apparatuses connected to a network or networks by using remote power source controllers operated by auxiliary power sources of the information processing apparatuses.
2. Description of the Related Art
Distributed processing systems having a plurality of computers connected by a network are widely used. In such a distributed processing system, a host has a function of managing and operating remote computers. One example of such a function of a host is to perform a power source control for remote computers.
As the technology concerning remote power source controls, there are known a centralized power-off scheme in which a server machine transmits a special command to a client machine to turn off the power source of the client machine, reference being made to JP-A-4-284520, a power source stop controlling means in which upon reception of a command inputted from an operation terminal, a machine checks its operation state and if the state is a command accepting state, the power source is turned off, reference being made to JP-A-4-289906, and a terminal equipment in which when a power source control signal is detected from packet data received from a communication line, the terminal equipment controls a power source control unit to turn on or off its power source, reference being made to JP-A-4-343115.
The above-described prior art, however, has have the following problems. The prior art of JP-A-4-284520 pertains only to a power-off control of a client machine by a server machine, and does not consider how security is protected.
Similar to the first prior art, the prior art of JP-A-4-289906 pertains only to a power-off control and requires a command input from an operation terminal. The prior art of JP-A-4-343115 is applicable only to a power control of a terminal equipment. Since this prior art uses a type field of an EtherNet frame, a specific control method is required to be used, and in addition, machines from different vendors are difficult to interconnect. Furthermore, if power is being supplied to a terminal equipment, the power source is turned off, whereas if power is not being supplied to the terminal equipment, the power source is turned on. It is therefore necessary to provide the power source control unit with a logic circuit for operation state judgement. Still further, since a method of supplying power to an EtherNet controller is unspecified, there may be some problem about a power-on control. In addition, security means is not taken into consideration.